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As the world's focus turns to the future and not the present, the engineering profession must respond to the ever increasing need to bring about a sustainable future. The objective of this paper is to support the reform of engineering education by acknowledging and building upon the current awareness and understanding of sustainable development held by key stakeholders in the process. This paper presents the outcomes of a study involving twelve focus groups with Academics, Employers and Students in four European countries (Denmark, Finland, France and Ireland) as part of the A-STEP 2030 European Project. Based on the findings, it is clear that the key stakeholders closely associate the theme of the environment with Sustainable Development. There is also mention of the pillar of economy, but less so, that of society. The findings also reveal differences in the awareness of specific Sustainable Development Goals (SDGs), with SDG 13 (Climate Action) being most widely noted. The findings allow educators to engage in discussion with students to build a more complete understanding of aspects of sustainable development and to act in redesigning curricula to ensure engineers can contribute to a sustainable future.

A precisely localized enzyme cascade was constructed by integrating two sequential enzymes, glucoamylase (GA) and glucose oxidase (GOx), on a yeast cell surface through an a-agglutinin receptor as the anchoring motif with cohesin-dockerin interaction. The overall catalytic activities of the combinant strains were significantly dependent on the assembly method, enzyme molecular size, enzyme order, and enzyme stoichiometry. The combinant strain with GA-DocC initially bound scaffoldin prior to GOx-DocT exhibited a higher overall reaction rate. The highest overall reaction rate (29.28 ± 1.15 nmol H2O2 min-1mL-1) was achieved when GA/GOx ratio was 2:1 with enzyme order: yeast-GA-GOx-GA, 4-fold enhancement compared to free enzyme mixture. Further, the first example of starch/O2 enzymatic biofuel cells (EBFCs) using codisplayed GA/GOx based bioanodes were assembled, demonstrating excellent direct biomass-to-electricity conversion. The optimized EBFC registered an open-circuit voltage of 0.78 V and maximum power density (Pmax) of 36.1 ± 2.5 μW cm-2, significantly higher than the Pmax for other starch/O2 EBFCs reported so far. Therefore, this work highlights rational organization of sequential enzymes for enhanced biocatalytic activity and stability, which would find applications in biocatalysis, enzymatic biofuel cells, biosensing, and bioelectro-synthesis.

Thermal oils due to their high ability in cooling and lubricating have many applications in high-tech industries such as automotive industry. Dispersing nanoparticles in a thermal oil (which the resulted new liquid is called nanofluid) can modify further the cooling and lubrication efficiencies. This review paper aims to present the recent advances in the preparation methods and thermophysical properties measurements of oil-based nanofluids. Effects of various parameters such as nanoparticle concentration, size, and temperature on the values of properties including thermal conductivity, viscosity, density, and specific heat are reviewed. The correlations available for the properties of oil-based nanofluids are gathered from the literature that could be a worthy source for those who aim to work on oil-based nanofluids.

The global effects of climate change will increase the frequency and intensity of extreme events such as heatwaves and power outages, which have consequences for buildings and their cooling systems. Buildings and their cooling systems should be designed and operated to be resilient under such events to protect occupants from potentially dangerous indoor thermal conditions. This study performed a critical review on the state-of-the-art of cooling strategies, with special attention to their performance under heatwaves and power outages. We proposed a definition of resilient cooling and described four criteria for resilience—absorptive capacity, adaptive capacity, restorative capacity, and recovery speed —and used them to qualitatively evaluate the resilience of each strategy. The literature review and qualitative analyses show that to attain resilient cooling, the four resilience criteria should be considered in the design phase of a building or during the planning of retrofits. The building and relevant cooling system characteristics should be considered simultaneously to withstand extreme events. A combination of strategies with different resilience capacities, such as a passive envelope strategy coupled with a low-energy space-cooling solution, may be needed to obtain resilient cooling. Finally, a further direction for a quantitative assessment approach has been pointed out. Peer Reviewed

In order to reduce the number of charge/discharge cycles of distributed energy storage systems (DESSs) to extend their lifespan, a State-of-Charge (SoC) balancing control is used. In conventional SoC balancing strategies, a local integral control is generally introduced in each DESS to ensure SoC equalization and Distributed Generators (DGs) frequency restoration. These strategies increase the system order and have a constraining bandwidth that may lead to stability issues. The few methods in which a local integrator is not added generally result in poor performance of the SoC synchronization strategy and frequency restoration, with the inability to eliminate static error. In this proposal, a novel resilient distributed control is proposed to ensure an effective SoC balancing of DESSs and frequency restoration with high performance without increasing the system order with a local integral control. The dynamic average consensus is modified to evaluate the participation level of each DESS in order to determine the active power references to synchronize the SoCs of the DESSs. These active power references are chosen to regulate the DG frequency to the nominal frequency of the MG. Therefore, the proposed method ensures SoC balancing with automatic frequency regulation and accurate output power sharing performance. Only voltage restoration control is added for DGs voltage regulation. In this distributed control architecture, SoC equalization as well as voltage/frequency restoration are performed only with local DG information and information from their neighbors. Simulations and then experimental results are performed to verify the effectiveness of the proposed method in discharging mode, in charging mode, in the presence of intermittent renewable energy sources, in the case of communication failure, in the case of communication delay, in the case of load variation, and in the case of “plug and play”. Comparisons were also made with two SoC balancing strategies from the literature.

In this work we address the problem of stimulating nervous tissue with the minimal necessary energy at reduced/minimal charge. Charge minimization is related to a valid safety concern (avoidance and reduction of stimulation-induced tissue and electrode damage). Energy minimization plays a role in battery-driven electrical or magnetic stimulation systems (increased lifetime, repetition rates, reduction of power requirements, thermal management). Extensive new theoretical results are derived by employing an optimal control theory framework. These results include derivation of the optimal electrical stimulation waveform for a mixed energy/charge minimization problem, derivation of the charge-balanced energy-minimal electrical stimulation waveform, solutions of a pure charge minimization problem with and without a constraint on the stimulation amplitude, and derivation of the energy-minimal magnetic stimulation waveform. Depending on the set stimulus pulse duration, energy and charge reductions of up to 80% are deemed possible. Results are verified in simulations with an active, mammalian-like nerve fiber model.